What is the proper CIDR prefix notation for a subnet mask of 255.0.0.0?

The proper CIDR prefix notation for a subnet mask of 255.0.0.0 is /8. This notation indicates that the first 8 bits of the subnet mask are set to '1' (or represent the network portion), while the remaining 24 bits are set to '0' (representing the host portion).

In the case of 255.0.0.0, the binary representation is as follows:

• 255 in binary is 11111111

• 0 in binary is 00000000

So, the subnet mask appears as 11111111.00000000.00000000.00000000, clearly showing that the first 8 bits are used for network identification. This means that a network using this CIDR prefix can accommodate a wide range of hosts within the same network, making it suitable for very large networks, such as those used by ISPs or large enterprises.

The other options represent different subnet mask configurations. For example, /16 indicates that 16 bits are for the network and would correspond to a subnet mask of 255.255.0.0, while /24 corresponds to 255.255.255.0, providing fewer available hosts. /